In some embodiments, a torque damper apparatus can achieve reduced stiffness as well as sufficient vibration absorbing property while increasing the dampening ratio of the torque variation. In some embodiments, a torque damper apparatus comprises an input member to which an engine torque is inputted; damper springs able to absorb variation of torque inputted from the input member; and/or a driving power of the engine configured to be transmitted to an output shaft of a vehicle via the input member and the damper springs. The damper springs can comprise a plurality of coil springs arranged along the circumference of the input member. The torque damper apparatus can further comprise a plurality of separate members interposed between the damper springs and configured to be independently rotated with respect to each other when the engine torque is transmitted thereto.

A damper assembly includes a driven plate, an intermediate plate, and elastic drive elements. The intermediate plate includes a radially outer base wall and opposite side walls. The elastic drive elements are interposed, between tabs of the driven plate and tabs of the intermediate plate to permit relative rotational movement therebetween. The elastic drive elements reside in cavities defined, in part, by a substantially annular radially inwardly facing surface of the intermediate plate. A first region of the radially inwardly facing surface in closest proximity to the elastic drive elements has a first radius. A second region of the radially inwardly facing surface axially interposed between the first region and the first side wall has a second radius that is greater than the first radius.

A torsional vibration damper, including: an axis of rotation; a drive plate; an output flange; and a spring retainer plate including a first side facing in a first axial direction, a second side facing in a second axial direction, and a plurality of spring stops formed of a same material forming the spring retainer plate. Each spring stop: extends from the first side at least partially in the first axial direction; and includes first and second circumferentially separated end surfaces separated, in the first axial direction, from the first side by first and second gaps, and a plurality of springs. Each spring includes a first circumferential end engaged with a respective first end surface and a second circumferential end engaged with a respective second end surface. The spring retainer plate partially surrounds the plurality of springs and retains the plurality of springs in a radially outward direction.

In a damper device, a dynamic damper is coupled to a first intermediate member, first and second inner-side springs that act in series with each other are straight coil springs disposed between a second intermediate member and a driven member so that outward movement of the springs in a radial direction of the damper device is restricted at respective both ends, and a gap is formed between each body portion of the first and the second inner-side springs and the second intermediate member or a spring abutment portion of the driven member.

A torsional-vibration reducing device includes: an input rotation member, an output rotation member, a coil spring which mitigates torque fluctuation generated at an input side and transmits power to an output side, a spring retaining portion provided on at least one of the input rotation member and the output rotation member and configured to support the coil spring, and a hole formed at a position corresponding to the spring retaining portion in an outer diameter direction with respect to a rotation center line.

In a method of assembling a damper device, a first support portion of a first rotor and a first accommodation portion of a second rotor are overlapped to eliminate an axial offset between them. A first elastic member is placed in the first support portion and the first accommodation portion. A second support portion of the first rotor and a second accommodation portion of the second rotor are overlapped to eliminate an axial offset between them by simultaneously compressing the first elastic member and rotating the second rotor relative to the first rotor to a first-side in a rotational direction. A second elastic member is placed in the second support portion and the second accommodation portion. Simultaneously, the second elastic member is compressed and the second rotor is rotated relative to the first rotor to a second-side in the rotational direction by angle corresponding to the offset between the first support portion and the first accommodation portion.